Physics- forces

• Drag forces and friction

  Proportional to the force applied to it
• Why do the speed and directions of motion of objects change?

  Forces acting on a body cause the motion of that body to change
• Upthrust


  • A force that pushes things up in liquids and gases
• Friction


  • A force that opposes motion between two surfaces that are in contact
• Weight


  • A measure of the force of gravity on an object
• Air resistance

  The force that opposes the object moving through the air
• Support force


  • The upward force that balances the weight of an object on a surface
• Driving force


  • A force that completely balances the weight of an object at rest
• Force


  A push or pull on an object
• We use to measure force

  Newton meter
• Balanced and unbalanced forces

  When the forces exerted on the object, are of equal size but in opposite direction
• What forces do


  Change the shape, speed or direction of an object
• Interaction pair


  • A pair of forces that are equal and opposite and act on two interacting objects
• How forces deform objects

  Bending, Stretching or compressing
• How solid surfaces provide a support force

  Exerts an upward for force called support force
• Hooke's Law


  Extension is proportional to force
• Why do drag forces and friction arise?

  The tension between the objects creates this force
• What is the effect of gravitational forces on the earth?


  They pull objects and people to the centre of the earth
• Equilibrium


  A state in which opposing forces or influences are balanced